The present invention relates to a method for cleaning piping and a cleaning system for piping.
Cleaning out of place (COP) and cleaning in place (CIP) are used as methods for cleaning facility and apparatuses in the manufacturing industry and other industries.
Cleaning out of place is a method of cleaning each part and component after disassembling equipment.
In contrast, cleaning in place is a method of performing cleaning without disassembling equipment, which is implemented by integrating cleaning functions into the equipment, or in food manufacturing facility and apparatuses composed mainly of pipings and containers found in the food manufacturing industry, food processing industry and like industries, cleaning is carried out by passing through the piping a cleaning solution at a high pressure from the outside.
In cleaning in place carried out in such food manufacturing industry and food processing industry methods using alkali cleaning whose target of cleaning is mainly organic matters, and acid cleaning whose target of cleaning is mainly inorganic matters, are widely employed in combination. In addition to the cleaning processes by alkali detergents and acid detergents, chlorine-based or iodine-based disinfectants are used for the purpose of disinfection of equipment, and surfactants are used for the purpose of deodorizing, including many other agents. These cleaning solutions, water used before and after cleaning processes for rinsing, and sterilizing steam has a temperature adjusted to increase cleaning efficiency. Normally, such liquids are heated to a high temperature for use, and are then cooled to be drained. Accordingly, considerable amount of time, agents, and energies are required for cleaning processes.
Conventionally, as a technique which is capable of performing cleaning with a high degree of cleaning, shortening the time for cleaning in place, and reducing the amounts of agents and other substances used during cleaning in place, there has been a cleaning method for on-site cleaning of equipment such as filling equipment that fills beverages, etc. into bottles, cans, and other containers, liquid treatment equipment for filling solutions, and pipe equipment for connecting the equipment, in which liquid comprising nanobubbles is conveyed into the equipment and is left undisturbed to soak for a prescribed period, and the gas of nanobubbles used being ozone gas so that a bactericidal action and a deodorizing action are added (refer to Japanese Unexamined Patent Publication No. 2012-45528).
Moreover, as a cleaning technique using ozone water, there has been a cleaning method for electronic materials such as silicon substrates for semiconductors and glass substrates for liquid crystals, the method comprising the steps of cleaning with ozone water containing an acid and cleaning with ozone water containing an alkali (refer to Japanese Unexamined Patent Publication No. 2002-001243).